使用自定义错误消息在WCF服务中进行验证

Question

I am having a Data Contract as below. I want to return a custom error message if Name is empty. How can i achieve that? Contract:

[DataContract]
    public class Employee
    {
        [DataMember]
        public int Id { get; set; }
        [DataMember]

        public string Name { get; set; }
    }

Response: ErrorCode: 111 ErrorDesc: null ErrorText: null StateCode: null

Answer 1

What you want to do is look at Fault Contracts,

A few links can be found on the net

1. https://www.c-sharpcorner.com/UploadFile/788083/how-to-implement-fault-contract-in-wcf/
2. https://docs.microsoft.com/en-us/dotnet/framework/wcf/samples/fault-contract
3. http://www.topwcftutorials.net/2014/07/wcf-fault-contract.html

But if that is a bit too much for what you want to achieve, you can look at DataAnnotation , putting

[DataMember]
[Required]
public string Name { get; set; }

Should be all that is required to force the user to create a value for

Name

Also note that there is an overload to the [Required] Attribute that uses a custom error message

[Required(ErrorMessage="You have not supplied a value for the Name parameter")]

You can also combine this with

[StringLength(20, ErrorMessage = "The Name value cannot exceed 20 characters. ")]

This would not look like

[DataContract]
    public class Employee
    {
        [DataMember]
        public int Id { get; set; }
        [DataMember]
[StringLength(20, ErrorMessage = "The Name value cannot exceed 20 characters. ")]
[Required(ErrorMessage="You have not supplied a value for the Name parameter")]
        public string Name { get; set; }
    }